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INAF – Osservatorio Astronomico di Trieste C. Morossi Chemical evolution in the Universe: the next 30 years 16-20 Sept, 2013 Castiglione della Pescaia,

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Presentation on theme: "INAF – Osservatorio Astronomico di Trieste C. Morossi Chemical evolution in the Universe: the next 30 years 16-20 Sept, 2013 Castiglione della Pescaia,"— Presentation transcript:

1 INAF – Osservatorio Astronomico di Trieste C. Morossi Chemical evolution in the Universe: the next 30 years Sept, 2013 Castiglione della Pescaia, Italy C. Morossi, M. Franchini, P. Di Marcantonio INAF-Osservatorio Astronomico Trieste, Italy M.L. Malagnini Dip. Fisica, Univ. Trieste, Italy & INAF M. Chavez INAOE, Mexico Lick/SDSS library v2.0: a new tool to compute model of stellar populations with variable Alpha element abundance ratios

2 INAF – Osservatorio Astronomico di Trieste C. Morossi Lick/SDSS Spectral Indices

3 INAF – Osservatorio Astronomico di Trieste C. Morossi library v1.0 (Franchini et al. 2010) Lick/SDSS library v1.0 (Franchini et al. 2010) Computed starting from synthetic spectra degraded at R=1800 (like SDSS) Two grids of HiRes synthetic spectra: Solar Scaled [ /Fe] = +0.0 (SSA) and -enhanced [ /Fe] = +0.4 (NSSA) starting from Kurucz atmosphere models (ATLAS9) computed with solar and - enhanced ODFs by Castelli (2003) using SPECTRUM V.2.75 (Gray and Corbally 1994) There is full consistency between synthetic spectra and the ODF of the atmosphere models Teff : K (250 K step) log g: dex (0.5 dex step) [Fe/H]=-2.5,-2.0,-1.5,-1.0,-0.5, [Fe/H]=-2.5,-2.0,-1.5,-1.0,-0.5,0.0,+0.2,+0.5 (NSSA) [Fe/H]=-2.5,-2.0,-1.5,-1.0,-0.5,0.0,+0.2,+0.5 (SSA). 0,+0.2,+0.5 (SSA) [Fe/H]=-2.5,-2.0,-1.5,-1.0,-0.5,0.0,+0.2,+0.5 (NSSA)

4 INAF – Osservatorio Astronomico di Trieste C. Morossi Stellar atmospheric parameters From Lick/SDSS library v1.0 we ( Franchini et al. ApJ 2011, 730, 117 ) derived the atmospheric parameters of more than 4000 F, G, and K SDSS stars by comparing synthetic and observed spectral indices Indices are negligibly affected by errors in flux calibration and by reddening Narrow-band indices allow the measurement of the intensity of features of different chemical species separately Indices are characterized by higher S/N than the original spectra Homogeneous and self-consistent atmospheric parameter estimates BUT...

5 INAF – Osservatorio Astronomico di Trieste C. Morossi library v1.0 main limitations Lick/SDSS library v1.0 main limitations Only 2 values of [ /Fe] All element abundances varying in lock steps Matching with observed values via ad-hoc calibration

6 INAF – Osservatorio Astronomico di Trieste C. Morossi Is the same for all the elements? Is [ /Fe] the same for all the elements? The [Mg/Fe] and [Ca/Fe] derived for more than 4000 F, G, and K SDSS-DR7 stars by means of library v1.0 are different ! The [Mg/Fe] and [Ca/Fe] derived for more than 4000 F, G, and K SDSS-DR7 stars by means of Lick/SDSS library v1.0 are different !

7 INAF – Osservatorio Astronomico di Trieste C. Morossi library v2.0 (in preparation) Lick/SDSS library v2.0 (in preparation) Kurucz atmosphere models computed with ATLAS12 Refined and more complete atomic and molecular line list HiRes synthetic spectra computed with SPECTRUM V.2.76e (Gray and Corbally 1994) several chemical compositions: Solar Scaled with [Fe/H] from +0.5 to -3.0 with Δ[Fe/H]=0.25 (SSA) -enhanced with [ /Fe] from +1.0 to -1.5 with Δ[α/Fe]=0.25 (NSSA) Individual -element enhanced (i.e. Mg, Si, Ca, Ti) full consistency between synthetic spectra and atmosphere models No need of ad-hoc calibration for most of the synthetic indices )

8 INAF – Osservatorio Astronomico di Trieste C. Morossi Are the new synthetic indices more reliable? Comparison with the observed ones requires: Good observations Accurate estimates of atmospheric stellar parameters

9 INAF – Osservatorio Astronomico di Trieste C. Morossi Good observations The UVES Paranal Observatory Project: A Library of High- Resolution Spectra of Stars across the Hertzsprung-Russell Diagram (2003) Bagnulo, S.; Jehin, E.; Ledoux, C.; Cabanac, R.; Melo, C.; Gilmozzi, R The Messenger (ISSN ), No.114, p The ELODIE Archive (2004) Moultaka, J.; Ilovaisky, S. A.; Prugniel, P.; Soubiran, C. The Publications of the Astronomical Society of the Pacific, Volume 116, Issue 821, pp. 693 The Indo-US Library of Coudé Feed Stellar Spectra (2004) Valdes, Francisco; Gupta, Ranjan; Rose, James A.; Singh, Harinder P.; Bell, David J. The Astrophysical Journal Supplement Series, Volume 152, Issue 2, pp Medium-resolution Isaac Newton Telescope library of empirical spectra - II. The stellar atmospheric parameters. (2007) Cenarro, A. J.; Peletier, R. F.; Sánchez-Blázquez, P.; Selam, S. O.; Toloba, E.; Cardiel, N.; Falcón-Barroso, J.; Gorgas, J.; Jiménez-Vicente, J.; Vazdekis, A Monthly Notices of the Royal Astronomical Society, Volume 374, Issue 2, pp

10 INAF – Osservatorio Astronomico di Trieste C. Morossi Accurate estimates of atmospheric stellar parameters (1) The Chemical Evolution of the Galactic Disk - Part One - Analysis and Results Edvardsson, B.; Andersen, J.; Gustafsson, B.; Lambert, D. L.; Nissen, P. E.; Tomkin, J. Abundances and Kinematics of Field Halo and Disk Stars I: Observational Data and Abundance Analysis Fulbright J.P.. The chemical compositions of Galactic disc F and G dwarfs Reddy, Bacham E.; Tomkin, Jocelyn; Lambert, David L.; Allende Prieto, Carlos Stellar chemical signatures and hierarchical galaxy formation. Venn K.A., Irwin M., Shetrone M.D., Tout C.A., Hill V., Tolstoy E. Alpha-, r-, and s-process element abundance trends in the Galactic thin and thick disks T. Bensby, S. Feltzing, I. Lundstrom, and I. Ilyin Giants in the local region. Luck R.E., Heiter U. Photospheric CNO abundances of solar-type stars. Takeda Y., Honda S. Fundamental parameters and elemental abundances of 160 F-G-K stars based on OAO spectrum database. Takeda Y. A holistic approach to carbon-enhanced metal-poor stars. Masseron T., Johnson J.A., Plez B., Van Eck S., Primas F., Goriely S., Jorissen A. Homogeneous photospheric parameters and C abundances in G and K nearby stars with and without planets. Da Silva R., Milone A., Reddy B.E. …

11 INAF – Osservatorio Astronomico di Trieste C. Morossi Accurate estimates of atmospheric stellar parameters (2) The comparison of our results with published high-resolution analysis results shows that some of the latter may be affected by systematic errors and/or a lack of self-consistency.

12 INAF – Osservatorio Astronomico di Trieste C. Morossi Accurate and complete atomic and molecular line list (1)

13 INAF – Osservatorio Astronomico di Trieste C. Morossi Accurate and complete atomic and molecular line list (22) Individual element abundancies Self-consistent models and spectra Empirical log gfs Different microturbulence velocity for giants and dwarfs

14 INAF – Osservatorio Astronomico di Trieste C. Morossi Preliminary results based on 222 bona-fide stars (1)

15 INAF – Osservatorio Astronomico di Trieste C. Morossi Preliminary results based on 222 bona-fide stars (2)

16 INAF – Osservatorio Astronomico di Trieste C. Morossi Thank you Chemical evolution in the Universe: the next 30 years Sept, 2013 Castiglione della Pescaia, Italy


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